The black cabbage tree blooms in October and November, bearing clusters of daisy-like flowers on the ends of the branches, surrounded by the leaves (2) (3). Each ‘flower’ measures around 1.2 centimetres across (2) (3), and, like other members of the Compositae family, is in fact a compound structure composed of many tiny, individual flowers known as florets (7). The ‘flower’ of the black cabbage tree is made up of around 60 to 75 central, yellowish disc florets surrounded by 20 to 25 white, petal-like ray florets (4) (5).
The seeds of the black cabbage tree often germinate on the trunks of tree-ferns, the weight of the black cabbage tree eventually causing the tree-fern to fall. The tree-fern and the cabbage tree both then continue to grow, the cabbage tree often rooting into the soil (1) (2) (3) (6).